Silica nanosheets (SN) derived from natural vermiculite (Verm) were successfully incorporated into polyethersulfone-polyvinylpyrrolidone (PES-PVP) polymer to fabricate high-temperature proton exchange membranes (HT-PEMs).The content of SN filler was varied (0.1-0.75 wt％) to study its influ-ence on proton conductivity,power density and durability.Benefiting from the hydroxyl groups of SN that enable the formation of additional proton-transferring pathways,the inorganic-organic membrane displayed enhanced proton conductivity of 48.2 mS/cm and power density of 495 mW/cm2 at 150 ℃without humidification when the content of SN is 0.25 wt％.Furthermore,exfoliated SN (E-SN) and sul-fonated SN (S-SN),which were fabricated by a liquid-phase exfoliation method and silane condensation,respectively,were embedded in PES-PVP polymer matrix by a simple blending method.Due to the sig-nificant contribution from sulfonic groups in S-SN,the membrane with 0.25 wt％ S-SN reached the high-est proton conductivity of 51.5 mS/cm and peak power density of 546 mW/cm2 at 150 ℃,48％ higher than the pristine PES-PVP membranes.Compared to unaltered PES-PVP membrane,SN added hybrid compos-ite membrane demonstrated excellent durability for the fuel cell at 150 ℃.Using a facile method to pre-pare 2D SN from natural clay minerals,the strategy of exfoliation and functionalization of SN can be potentially used in the production of HT-PEMs.